The proposed regulations make investments in upgrading urban levees in West Sacramento and Stockton and adjacent areas “very high priority.” These investments are long needed, particularly for Stockton. Stockton is the 7th largest city in California, and the levees are badly in need of improvement.

Funding for improvements to urban levees has typically been tied to federal projects and funded separately from improvements to levees in the primary zone of the Delta. Improvements to the levees in the primary zone have been funded by the Delta Levees Subvention and Special Projects Programs, separate pots of money.

The Delta Levees Investment Strategy also prioritizes investments in improving levees protecting Bethel Island in the South Delta. The US Census estimated Bethel Island’s population at 2,379 in 2017. This is also an important investment.

But Rio Vista, population 9,009, and Discovery Bay, population 15,525, are second priority for levee improvements. And the Delta legacy towns of Clarksburg, Courtland, Locke, and the eastern bank of Walnut Grove are the lowest priority, even though Clarksburg and Courtland have public schools. (Walnut Grove is on both sides of the Sacramento River.)

Delta Levee Investment Priorities — Closeup of North Delta

Delta Levee Investment Priorities — Closeup of South Delta

The Central Delta Water Agency has commented that, given the shortage of funds for the Delta Levees Subvention and Special Projects Programs, no or almost no funds will be available for levee improvements for islands in the second tier, and none for the lowest tier. Thus the Delta Levees Investment Strategy codifies the somewhat chilling calculus that protecting smaller, vulnerable Delta communities from flooding is not in the state interest.

One of the main reasons there are insufficient funds to protect smaller Delta communities is that the Delta Levees Investment Strategy also assumes that public funds must be spent to protect Delta exports and pay for mitigation of impacts of the State Water Project and Central Valley Project.

According to the proposed Delta Levees Investment Strategy regulations, the levees on these islands must be fully improved before any state funds can be spent improving levees protecting Rio Vista, Discovery Bay, Clarksburg, Courtland, Locke, or the east bank of Walnut Grove.

The “Ability to Pay” analysis for the Delta Levees Investment Strategy did not take into account that revenues from the State Water Project could be used to improve the Delta islands that are “critical for water supply,” even though two of the islands are owned by the Department of Water Resources. Most of the land on Sherman and Twitchell Islands was acquired by DWR in the early 1990s. The acquisition and conversion of the lands to grazing and wildlife uses allowed the Department of Water Resources to move the salinity compliance point for their contract with North Delta Water Agency upstream. This was estimated in to provide a benefit to critical period SWP deliveries of more than 100,000 acre-feet per year.

The Delta Levees Investment Strategy also makes public investments in tidal habitat restoration on Dutch Slough and McCormack-Williamson Tract highest priority. These islands are being restored as part of 8,000 acres of intertidal and subtidal habitat restoration required for mitigation of the impacts of the State Water Project and Central Valley Project. The Ability to Pay analysis for the Delta Levees Investment Strategy includes no revenues from the State Water Project for the habitat restoration, even though mitigation of impacts of the State Water Project is legally the responsibility of the State Water Project Contractors.

Thus the result of the analysis for the Delta Levees Investment Strategy combining pots of money for upgrades to urban Delta levees, upgrades to levees in the Delta primary zone, and habitat restoration, is that funding for protecting smaller Delta communities basically vanishes. Combining the pots of money is contrary to the originally recommended cost allocation methodology for the DLIS, the Separable Costs — Remaining Benefits method (SCRB.) Under SCRB, costs and benefits of projects for water supply reliability and habitat restoration would have been analyzed both jointly and separately from protection of lives and property.

The DLIS also exposes the state to considerable liability. Many of the levees protecting North Delta legacy communities are State Plan of Flood Control Levees. The Central Valley Flood Control Association commented that “[d]eviating from existing definitions of levee maintenance that results in the state reducing investments in maintenance of SPFC levees will ultimately increase state liability and costs to pay for flood damage caused by levee failures.” The Central Valley Flood Control Association comments reference the 1986 SPFC Project levee failure near Yuba City “which resulted in evacuations, deaths, and hundreds of millions of dollars in property losses.” In the Paterno decision, this failure to adequately maintain the State Plan of Flood Control Levees resulted in liability by the state of $467 million.

Following the originally proposed SCRB cost allocation method would have avoided the issue with prioritizing non-project levees which protect water supply over SFPC levees which protect lives and property. The slide below is from a presentation by Arcadis consultants for the Delta Science program peer review of the DLIS methodology.

Slide from presentation to Delta Stewardship Council on DLIS methodology

Because of the failure to follow the recommended cost allocation procedure, it is difficult to see how the DLIS is consistent with the legislative mandate that the Delta Plan “attempt to reduce risks to people, property, and state interests in the Delta by promoting effective emergency preparedness, appropriate land uses, and strategic levee investments.”

This post was updated on 8/21 to include links to comment letters on the Delta Levees Investment Strategy, more maps, and information on the originally proposed method of cost allocation.